Pneumatic tire.



No. 879,199. PATENTED FEB. 18, 1908.

B. P. SCHIRMER. PNEUMATIC TIRE.

APPLIUATION FILED APR. 15. 1907.

f and has the usual opening for the piston rod v Indianapolis, couny *munie ate At one side y'of this OFFICE.

BALDWIN F'. scHiRMER, or INDIANAPOLIS,- INDIANA;

\ PNEUMAT'IC TIRE.

No. arenas.

"Spcification of Letters Patent.

Patented Feb. 18,1908.

Ap'pnmm med April 15. 1907. "serial No. 368.221.

To all 'whom it may concern: 4

Be it known that I, BALDWIN F. SCHIRMER, a citizen of the United States, and'resident of of Marion, State of Indiana, have invente certain new anduseful Improvements in Pneumatic Tires, of which I hereby declarethe following to be a full, clear, and exact descri tion, such as will enable others skilled in t e art to which it appertains to make and use the same.

The invention relates to improvements iny pneumatic tires and the invention is designed to employ a series of inllated b'u'er springs or compressed air cylinders havin pistons therein and arranged about the rim of the wheel, and having a common annular air chamber for lthecylinders as `described in a previous application Serial No. 286,025.

The particular objects of this invention are to providecirculating passages and a valve system whereby the air from outside the tire can be continually pumped into this annular chamber to take the'place of air whichvhas" leaked out of the tire ,and'in this manner maintain a permanent resistance in the buffers. To accomplishthis object,` I employ the arrangement 'of circulating passa es and inlet and outlet. valves, as hereina t'erde# scribed' and specifically pointed out in the claims. n

ln the accompanying drawings, Figure 1 is a transverse section of tire upon the central line of one of the cylinders; Fig. `2 is a longitudinal section; through thecenter of the tire and rim. g f

In these views 1 is the rim, 2 the tire casing, 3 a series of cylinders -having a common metallic ring 4 in which thy are secured and in which the chamber 5 common to all of the cylinders is formed. A iston within `each cylinder is provided wit a pro'ecting stem 7 and with abroad shoe 8 which with the other pistons distend the tirevand yield in succession to pressure when,v weight is brought to bear upon them. A cylinder head (9) 'closes the outer end of each cylinder,

or stem 7 to pass through.

Each .cylinder communicates with the common chamber 5 by means of an o ning 10 so that the resslre' in that cham er is com-4 wit e ual power to `each piston.- ycommon chamber; is

I shown a similar annular chamber 11, communicating with the outer end of each cylinder. above each piston b meansof. the lateral assage 12in each cylin er, which is controlled u per end of each cylin er with thecommon clamber A 5 and is controlled by means of a valve 15. the annular chamber 11 and the action ofthe several pistons when depressed into their `flow of air .into thecylinder above each 4piston through the passages 12, and when the pistons rise again in their respective cylinders the air will be drawn into the Acommon chamber l5 through the passages 14. This repeated action will maintain the pressure in the common chamber unreduced in strength so .that the 'inevitable continuous leaka e of a'pneumatic tire will be offset by the slight continuous renewal of air thereto. A separate inlet valve 17 may be employed supplied to the common chamber. and thus maintain the outward pressure upon the pistons sullicient to force the air out of the upper ends of the cylinder as the pistons rise.

` I' do not claim the exact arrangement or proportions of the various passages and valves, but

What I claim as new and desire to secure by-Letters Patent is ,1. The combination, with a'rimV and tire casin of a ring upon said rim, a series of cylin ers set therein at frequent intervals, a common chamber inclosed in said ring for all said cylinders and communicating with the inner ends of said cylinders, a piston lin each cylinder, ar stern and broadened shoe therefor, a casing against which said shoes are ad aptedto exert pressure, an annular cham-4 ber in said ring, communicating withthe outer ends of said cylinders, and having an inlet valve, assages leading from the outer ends of saidp cylinders to lthe saidv aforesaid common char'nbers sages. Y

2. The combination in a pneumatic tir'eof a casing and rim therefor, a ring encircling the saidrim, cylinders mounted atintervals y means of a valve 13, and a similar passage. 14 in the Wall of each 'dylinder connects the Y respective cylinders causes an automatic. 1

by means of which the initial pressure can be and-,valves 'in said p rs1- in said ring,'\ pistons .and pistonf` stems insaid` cylinderabroadened shoes for said ste'ms f And inlet valve 16 admits air to adapted to engage said easing, a common anpressed air passage, and valves in said pasnular compressed air chamber in said ring, sages. 10

communicating -With each of said cylinders at In testimony whereof I hereunto set my their lower ends, an air inlet chamber comhand this 10th. day of April, 1907.

munieating with each of said cylinders at kBALDWIN l". SCI-IIRMER. their outer ends, an inlet valve for said inlet In presence ofchamber and passages connecting the 'outer C. II. OLDS,

ends of seid cylinders with the common eom-l WM. M. MONROE. 

